TM 5-3805-260-24TORQUE CONVERTERThe torque converter connects the engine to theplanetary transmission. This connection between theengine and the transmission is a hydraulic connection.There is no direct mechanical connection between theengine and the transmission.The torque converter uses oil to send torque from theengine to the transmission. When the machine isworking against a load, the torque converter can multiplythe torque from the engine and send a higher torque tothe transmission.POWER FLOW THROUGH TORQUE CONVERTER1. Torque converter housing. 2. Flywheeladapter gear. 3. Gear for the transmission oilpump. 4. Rotating housing. 5. Drive gear for theoil pumps. 6. Stator. 7. Outlet passage. 8.Carrier. 9. Output shaft. 10. Inlet passage. 11.Turbine. 12. Gears (two) for the hydraulic pump.13. Impeller.The oil for the operation of the torque convertercomes from the oil pump for the transmission. The oilpump is driven by gear (3) and gear (5). An inlet ratiovalve (part of the pressure control valve in thetransmission) controls the maximum oil pressure to thetorque converter. An orifice in the outlet passagecontrols the minimum oil pressure in the torqueconverter.The rotating housing (4) is connected to the engineflywheel with splines of gear (2). The impeller ( 13) andthe drive gear (5) for the oil pump are connected to therotating housing. These components turn with theengine flywheel at engine speed.The stator (6) is connected to the carrier (8) which isconnected to the torque converter cover. The statordoes not turn.The turbine (11) is connected to the output shaft (9).Drive gear (5) is fastened to the impeller and turns thegears (3) and (12) for the oil pumps.Oil from the hydraulic controls of the transmissiongoes into the torque converter through an inlet passage(10) in the carrier (8).The impeller (13) [which turns with the rotatinghousing (4) at engine speed] makes the oil go toward theoutside of the impeller, around the inside of the rotatinghousing (4), and against the blades of the turbine (11).The oil that hits the turbine blades causes the turbine(11) and the output shaft (9) to turn. This sends torquethrough a drive shaft to transfer gears and to the inputshaft of the transmission.TORQUE CONVERTER4. Rotating housing. 6. Stator. 11. Turbine. 13. Impeller.After the oil hits the turbine blades, the oil goestoward the inside of the turbine (11). As the oil goesfrom the turbine, it moves in a direction opposite thedirection of impeller rotation. The stator (6) causes theoil to change direction and go back into the impeller (13)in the direction of rotation. This gives an increase to theimpeller oil output which gives an increase to the torqueoutput from the turbine (11).The larger the difference between the speeds ofrotation of the impeller (13) and the turbine (11) thelarger the output torque becomes.Oil from the outlet passage (7) goes to the oil cooler.2-83